A suicide blast in Mardan, Pakistan, has left at least 26 people dead and more than 20 others wounded.

The blast in the city northwest of Islamabad occurred outside the door of a government office called the National Database and Registration Authority or NADRA, which is responsible for issuing national identity cards.

Deputy Inspector General Mardan Division Saeed Wazir told local media the attacker was on a motorbike and exploded his explosives vest when he rammed at the gate. He added that authorities have identified the remains of the bomber and an investigation is underway.

First responders quickly cordoned off the area and moved the wounded to hospitals for treatment. Eyewitnesses reported seeing human remains strewn across the blast site. Some of the injured are in critical condition leading to fears that the death toll may rise.

Jamaat ul Ahrar, which is part of the anti-state alliance of Islamist groups called Tehreek-e-Taliban Pakistan (TTP), has claimed responsibility for the bombing.

In a statement sent to VOA, the group’s spokesman said it targeted NADRA’s office because it is part of Pakistan’s anti-terrorism war.

But the spokesman for the mainstream TTP, Mohammad Khorasani, in a separate statement to VOA, said the group had nothing to do with the Mardan bombing because "targeting civilians is not our policy."

Mardan, Pakistan

TTP has been waging a violent insurgency that has killed thousands of Pakistanis in recent years.

In a statement sent to reporters earlier on Tuesday, TTP claimed its suicide and other attacks during 2015 killed nearly 700 people in Pakistan. It added that most of those killed were linked to security and political institutions. The militant alliance is known to inflate death tolls.

Pakistani officials say their counter-insurgency operations mainly focusing on volatile tribal regions on the Afghan border have uprooted terrorist training facilities, leading to “a 70 percent” reduction in violence around the country.